Manufacture of hypodermic needles



May 1', 1956 s. J. Evl-:RETT 2,743,517

MANUFACTURE OF HYPODERMIC NEEDLES Filed May 1. 1953 4 sheets-sheet 1 MUMa www" U U J A Horne y May 1, 1956 s. J. EVERETT 2,743,517

MANUFACTURE OF HYPODERMIC NEEDLES Filed May l, 1953 4 Sheets-Sheet 2Attorney May 1, 1956 s. J. EVERETT 2,743,517

MANUFACTURE OF HYPODERMIC NEEDLES Filed May l, 1955 4 Sheets-Sheet 3 n@R QM B" A ttor/wy May 1, 1956 Filed May 1, 1953 S. J. EVERETTMANUFACTURE OF HYPODERMIC N EEDLS 4 Sheets-Sheet 4 'i ,M y

Inventor QQMJRQM By A Homey United States Patent O MANUFACTURE FHYPODERMIC NEEDLES Samuel James Everett, Thornton Heath, England,assigner `to S. & R. 3. Everett & Company Limited, Thornton Heath,England, a British company Application May 1, 1953, Serial No. 352,439Claims priority, application Great Britain May 6, 1952 7 Claims. `(Cl.29-528) This invention relates to the mounting of hypodermic needles inthe mounts whichenable themto be attached to the outlet of a hypodermicsyringe, and is particularly concerned with the manufacture of needlesand mounts in which a comparatively soft metal bush surrounds the needlewhere it emerges from the mount and extends a short distancetowards thepoint of the needle, as described in the specification of British PatentNo. 651,605 granted to Samuei I ames Everett.

These needles are usually packed in clips on a metal or plastic cardwhich can be packed in a box or container, preferably of metal; aconvenient number for each box is twelve needles mounted on a singlecard in six clips at either end. These needles have previously beenmanufactured singly, the soft metal bushes being die-cast, a number at atime, on a single runner, separated intoV individual parts, a needleinserted into each bush, and the whole inserted in the mount and swagedinto position individually. In such needles in which the point is formedby grinding the needle away at an angle, a fiat formed on the mountshould face radially in the same direction as the face formed bygrinding the needle.

The present invention enables a much higher rate of production to beachieved by manufacturing the needles and mounts in batches whichconveniently correspond to the number heid in clips at one end of thepacking card, which in the example quoted above, would be six. Thehandling of the parts during manufacturing is reduced, as well as therisk of damaging the needle points.

According to the invention, the complete needles are manufactured insets or batches and, to keep the needles together in their sets andlocated relative to each other, so that the complete set is easilyhandled and' the needles are correctly spaced for tting into the varioustools, the soft metal bushes are cast around the needles of a set on acontinuous runner from which they are not separated until the needlesand mounts are complete.

The number of needles in a set may conveniently be the number requiredat a time for packing. Thus when the needles are packed in dozens, sixin clips on each side of the box, it is convenientv to make the needlesin sets of six, and the various stages in the manufacture of a set ofsix needles is illustrated, by way of example only, in the accompanyingdrawings in which:

Figure l shows six needles set in a mould in which the metal bushes havebeen cast on a common runner;

Figure 2 shows the six needles with the bushes round them on a commonrunner;

Figure 3 shows the runner and needles mounted in a die-nest; f

Figure 4 shows the iirst stamping process;

Figure 5 shows the second stamping process;

Figure 6 shows the itting of the mounts;

Figure 7 shows diagrammatically a six-hammer press;

Figure 8 shows an enlarged detail of Figure 7;

Figure 9 shows a set of spring clips for holding the finished needles; l

Figure 10 shows the needles mounted for inspection;

Figure 1l shows a loading jig open;

, Figure vl2 showsa loading jig closed; and

released a spring 36 causes it to turn to raise the punch Patented May1, 1956 introduced through the hole 7.. The result is `a runner 8,

from which the six bushes 9 project, surrounding the shafts of theneedles 1 which pass right through the bushes and project slightly fromthe upper surface as seen in Figure 2. AThis is now set in the die-nestshown in Figure 3, consisting of a die-body 10, having six suitably Yspaced cavities 11, in which are die-inserts 12, the tops of whichprojects above die-body 10. These inserts have a central hole to takethe shafts of the needles and are coned at the top as shown at 13, so asto form a sharp edge round the ring of a diameter rather greater thanthe diameter of the metal bushes 9. This die-nest with the runner andneedles in place, is now passed to a first punch which cornes down onthe needles `1 as shown in Figure 4. The punch has a cavity 14, whichpasses over the bushes 9, and the tip of the punch bears on the runnercausing the coned head of the insert 13 to penetrate a short distanceinto the runner. The primary purpose of this punch, however, is to forcethe upper end of the needle shaft down llush with the top of the bush 9.

' The next punch shown in Figure 5 comprises a central punch 15, thehead of which is coned so as to drive the shaft of the needle yetfurther down through the bush 9. This punch is surrounded by a sleeve16, which is urged by a spring downwards over the head of the punch 15.Except for an axial bore fitting roundthe head of the punch l5, thelower end of the sleeve 16 is closed. The axial bore is coned at thislower end so as to fit over the bush 9. The sleeve 16 is free to slideon the punch i5 but its movement is limited by the pin 17, carried bythe punch 15 and projecting through a slot 18, in the sleeve. When thispunch is bearing down onto the head of the bush 9, the coned part of thesleeve 16 tits over the bush 9 and squeezes it slightly into the needleand serves to locate the axial bore accurately relative to the bush 9.When the sleeve 16 can descend no further the punch 15 continues todescend and engages the head of the needle shaft 1 and forces it part ofthe way through the bush 9 as shown, at the same time forming a conedrecess in the top of the bush. The pressure exerted in this operationcauses the sharp lim of the insert 12 to penetrate still further throughthe runner 8.

After this operation the dienest with the needles and runner is removedfrom the press, and turned brass or stamped metal mounts 19, are fittedover the bushes 9. The assembly then passes to the G-hammer press shownin Figures 7 and 8. ln Figure 7 the mechanism of the press is showndiagrammatically and comprises a vertical bar 20, arranged to slidevertically in guides and carrying a punch 21 at its lower end. The punch21 is locked into the lower end of the bar Ztl by a set screw 22. Aboveeach bar a hammer 23 is mounted, pivoted to turn aboutl an axis 24, andactuated by a push rod 25, having a follower roller at its lower end 26,which rides on the surface of a triple throw cam 27 on shaft 28. Toraise the punches clear of the work a rocker arm 29 is provided pivotedat 3d and having one end engaging in a notch 3l of the vertical bar 20.The other end of the rocker arm 29 is engaged by the upper end of thecontrol rod 32, which is connected at its lower end by a link 33 to apedal 34 pivoted at 35. Thus when the pedal is depressed as shown inFigure 7 the punch 21 is lowered and the follower 26 engages the surfaceof the cam 27. When the pedal 34 is 21 fand the hammer -23 is =lifted bythe vertical bar A20 SQ tbatttie .follswsr 2 6 .is r.Carrisfl clear Ofthe .Cam 27 The action of the punch 21 is shown in Figure 8. it has acylindrical part 37, whichenters the bore of the metal mountand the-conedtipof tlreipart-SY engages the bush 9 swaging it into tight andintimate `contact with themount 19, and the shaft of the needle 1. Threeblows of the hammers 23are sufficient, that is to say one revolution ofthe shaft 28, 'and this `also causes the head of the vclieinsert 12finally top'enetrate through the runner 8 as shown in FigureS.ThexpunchiZl is ncwraised again and the holder 38, having six springclips 39 spaced at the same intervals as the mounts 19,`is vfitted onthe mounts 19 which a'r'e thencremoved from 'the die-nest. The runner 8is left behind and `can be returned for remelting.

The pointsofthe needles are new passed'over a boiling wheelto removeanyburrs and the needles are'now tested, after which they are passed"for inspection still set in the holder 38, and `mounted on theinspection jig shown in Figure 10 comprising six spigots 4d mounted on abar 41. The spacing of the spigots is the same as ihespacing o f theclips 39, so that the needlesmay `be mounted directly on these spigotsand the holder 38 removed. The spigots are arranged so that whentheineedles are'mounted on them they are immediately beneath -a powerfulmagnifying glass through which `they are inspected. The needles can befreely rotated on the spigots 4t) for this purpose. After inspection theholder 38 is retitted and the needles removed and they `are thentransferred to the apparatus shown in `Figures 11 -and 12 for arrangingsuitably for packing in at tin boxes. Figure 13 shows the arrangement ofspringclips 43 projecting upwards from a card of plastic material '42,through holes in which the spring clips project. Six needles aremountedat each side of the card 42`With their points projecting inwards, and,in

the example shown, for economy of space alternate needles at each nsideare staggered as shown, so that the mounts do'notv foul each other. Thespacing of the clips 43`in each set of six clips is thus staggered andcloser together than the spacing of the spring clips 39 lon the holder38. The apparatus shown in Figures 11 and 12 is designed to receiveneedles from the holder 38 and adjust their spacing automatically tocorrespond with the arrangementof the spring clips 43.

The apparatus consists of 6 metal bars 44 mounted between guides 45 andeach provided at one end with a spigot 46 to fit a needle mount. Theright hand bar as seen in Figure l1 is secured to the guides 45 and thebars are linked together by pivotedtoggle links 47 as shown. The lefthand bar is provided with ahand knob 48 and its movement towards theleft in Figure 1l vis limited by a stop bar 49. In the-'position ofFigure y1l 'all the spigots 46 are in line and spaced' to correspond tothe spacing of the clips 39 of the-holder 38, so that the needles heldin the holder 38 can be fitted directly onto'the'spigots 46. When thishas been done the holder SS-is removed and the 'knob 48 pushed towardsthelrignt closing up the spacing of the bars 44, which are of Stichwidth that when they are together the'mounts are spaced a distance apartequal to the separation of the spring clips 43, while the togglelinkages 47 cause alternate mounts to be staggered as shown, so that themounts are all ready to have the spring clips 43 applied to them. Allsix needles'are thus mounted on the card 42 at A'or'tceland are 'thenremoved from the loading jig. A further six needles are litted to theclips on the opposite side of the card 42, which is then packed in itsbox.

This method of adjusting the spacing of the needles by simultaneouslymoving the members carrying the spigots 46 can be achieved in variousother Ways; for instance, by cams or other types of linkage such as alazy tong. The mechanism chosen will depend of course, on thearrangement of the needles when they are packed, and may be used toincrease thedistance` between the needles as well as to decrease it.This may be necessaryv inpacking needles in sterile foilorplasticspacks, when -the needles, in sets of, say, six, are spacedside by side without Staggering and .packed keach in an envelope of foilor thermoplastic material the envelopes being made in strips and latersevered from eah other. spacing of the needles during manufacture asdescribed may be one half inch, which may have to be increased to oneand a quarter inches for packing in this way.

The method of manufacture according to the invention is applicable toany type of needle in which the needle shaft is held in the mount by acast bush. Thus double ended needles for use for injection from ampoulesmay be made in this way, either with turned or stamped mounts of thetype shown, or with a central ball for mounting, or with a centraltransverse plate or `cam for engaging the syringe outlet.

I claim:

1. A process of securing hypodermic needles into mounts by which theymaybe `attached to a hypodermic syringe, by means of softmetal bushes`surrounding the shafts -of each needle, the Abushes being swaged intobores 'in said mounts comprising casting a plurality of said bushesaround alike number of said needles simultaneously on onecontinuous-runner atpoints intermediate the ends'of said needles,sliding said needles axially in said bushes to position said bushes atthe rear ends of said needles, yfitting a mount over each of saidbushes, swaging said bushes intointimate contact with said needles andVsaid mounts, and separating said bushes from said runner.

2. A process accordingtoclaim 1, in which the bushes are separated fromtherunner during the swaging operation. v

3. A process according toclaim.2, in which each bush is separated fromthe runner by the `sharp edge of one of a set of `circular dies 4throughwhich the shafts of the needles are passed, and on which the runnerrests during the fitting of the-mounts :andswaging of the bushes.

4. A process according-to claim 1, in which, afterthe bushes havebeencast, theshafts of the needles are pressed through the bushes soasto be flush with thc ends of the bushes, after which the Jneedlesareprcssed through the bushes still furtherfand the mouth-of the lboresof the bushes opposite to'the points of the needle shafts are axiallyconed.

5. A process according to claim `4, in which the runner rests on thediesduring the pressingoperation and is partially cut'throughiby thedies during this operation.

6. A process aceordingto claim 2, in which after the bushes have beenseparated from the runner, needles are graspedfand held in a like numberof similarly positioned spring clipsfrom `whichthey-are transferred to alike number of parallel spigots, after which thc positions of thespigots `are l simultaneously adjusted to move the needles into lthecorrectpositionffor packing, the number of needles in a setcorrespondingto the number required for packing at' onetime.

7. 'A processaccordinglto claim 6,-in which the needles are eventuallypacke'd lside 'by 'side 4in rows, alternate needles beingstaggered, andthe `spigots on which they are mounted prior t'o packing arerarranged onparallel members linked "by toggle linkages so that when thcIinkages'are extended,fthe spigots are side-by-side in line withfaspacing equal to thespacing ofthe bushes on the runner, and when themembers are close together thc toggle linkages 'move lthe spigots, andtherefore the mounts, into a position in which the needles are spacedand staggered 'readyfor-packing.

References' Citedn the tile of this patent UNITED STATES PATENTS1,782,447 Scrantom Nov. 1930 2,040,165 Baldwin e May 12, 1936 2,137,538`McIntosh Nov. 22, 1938 2,177,191 Sandberg -..u Oct. 24, 1939 2,226,849Douglas en A Dec. 31, 1940 For example, the

